CVE-2026-84131

Analyzed Analyzed - Analysis Complete

Privilege Escalation in Firefox Due to Invalid Pointer in Graphics

Publication date: 2026-09-01

Last updated on: 2026-09-03

Assigner: Mozilla Corporation

Description

Privilege escalation due to invalid pointer in the Graphics component. This vulnerability was fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.

CVSS Scores

EPSS Scores

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Meta Information

Published

2026-09-01

Last Modified

2026-09-03

Generated

2026-09-21

AI Q&A

2026-09-01

EPSS Evaluated

2026-09-20

NVD

CVE-2026-84131

EUVD

EUVD-2026-69067

Affected Vendors & Products

Vendor	Product	Version / Range
mozilla	firefox	From 154.0.0 (inc) to 155.0.0 (exc)
mozilla	thunderbird	From 154.0 (inc) to 155.0 (exc)
mozilla	firefox	From 141.0.0 (inc) to 153.2.0 (exc)
mozilla	thunderbird	to 140.15.0 (exc)
mozilla	thunderbird	From 141.0 (inc) to 153.2.0 (exc)
mozilla	firefox	to 115.40.0 (exc)
mozilla	firefox	From 116.0 (inc) to 140.15.0 (exc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-763	The product attempts to return a memory resource to the system, but it calls the wrong release function or calls the appropriate release function incorrectly.

Attack-Flow Graph

Executive Summary

This is a privilege escalation vulnerability caused by an invalid pointer in the Graphics component of Firefox. It allows attackers to gain higher privileges than intended, potentially leading to unauthorized system access or control.

Detection Guidance

This vulnerability is specific to Firefox versions before 155, Firefox ESR 115.40, Firefox ESR 140.15, and Firefox ESR 153.2. Detection involves checking installed Firefox versions. Use commands like 'firefox --version' or 'apt show firefox' (Linux) to verify versions.

Impact Analysis

If exploited, this vulnerability could let attackers execute arbitrary code, install malware, or access sensitive data on your system. Users running vulnerable Firefox versions should update immediately to mitigate risks.

Compliance Impact

The provided CVE data does not specify how this vulnerability impacts compliance with standards like GDPR or HIPAA. The vulnerability involves privilege escalation due to an invalid pointer in the Graphics component, but no direct compliance implications are mentioned.

Mitigation Strategies

Update Firefox to version 155 or later, Firefox ESR to version 115.40 or later, Firefox ESR to version 140.15 or later, or Firefox ESR to version 153.2 or later to address the privilege escalation vulnerability.

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